//
//  CoreDataManager.m
//  CoreData0825_58
//
//  Created by dllo on 15/11/20.
//  Copyright (c) 2015年 lanou3g. All rights reserved.
//

#import "CoreDataManager.h"
#import "Message.h"
@implementation CoreDataManager

+ (CoreDataManager *)defaults {
    static CoreDataManager *manager;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        manager = [[CoreDataManager alloc] init];
    });
    return manager;
}


- (void)addMessage:(NSString *)mes fromName:(NSString *)from toName:(NSString *)to {
    
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Message" inManagedObjectContext:self.managedObjectContext];
    
    Message *message = [[Message alloc] initWithEntity:entity insertIntoManagedObjectContext:self.managedObjectContext];

    message.mes = mes;
    message.from = from;
    message.to = to;
    
    NSDate *date = [NSDate date];
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:@"YYYY-MM-dd-HH-mm-ss"];
    NSString *time = [dateFormatter stringFromDate:date];
    
    message.time = time;
}

- (NSArray *)selectMessageWithFormat:(NSString *)formatString {
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Message" inManagedObjectContext:self.managedObjectContext];
    [request setEntity:entity];
    
    NSPredicate *predicate = [NSPredicate predicateWithFormat:formatString];
    [request setPredicate:predicate];
    
    NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"time" ascending:YES];
    [request setSortDescriptors:[NSArray arrayWithObjects:sortDescriptor, nil]];
    NSError *error = nil;
    NSArray *fetchObjects = [self.managedObjectContext executeFetchRequest:request error:&error];
    if (fetchObjects == nil) {
        NSLog(@"Core Data error === %@", error);
    }
    return fetchObjects;
}











#pragma mark - Core Data stack

@synthesize managedObjectContext = _managedObjectContext;
@synthesize managedObjectModel = _managedObjectModel;
@synthesize persistentStoreCoordinator = _persistentStoreCoordinator;

- (NSURL *)applicationDocumentsDirectory {
    // The directory the application uses to store the Core Data store file. This code uses a directory named "com.lanou3g.CoreData0825_58" in the application's documents directory.
    return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}

- (NSManagedObjectModel *)managedObjectModel {
    // The managed object model for the application. It is a fatal error for the application not to be able to find and load its model.
    if (_managedObjectModel != nil) {
        return _managedObjectModel;
    }
    NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"Model" withExtension:@"momd"]; // 编译时的文件格式
    _managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
    return _managedObjectModel;
}

- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
    // The persistent store coordinator for the application. This implementation creates and return a coordinator, having added the store for the application to it.
    if (_persistentStoreCoordinator != nil) {
        return _persistentStoreCoordinator;
    }
    
    // Create the coordinator and store
    
    _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
    NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"CoreData0825_58.sqlite"];
    NSError *error = nil;
    NSString *failureReason = @"There was an error creating or loading the application's saved data.";
    
    // 版本迁移的时候,配置信息
//    NSDictionary *options = [NSDictionary dictionaryWithObject:@(YES) forKey:NSMigratePersistentStoresAutomaticallyOption];
    
    if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:nil error:&error]) {
        // Report any error we got.
        NSMutableDictionary *dict = [NSMutableDictionary dictionary];
        dict[NSLocalizedDescriptionKey] = @"Failed to initialize the application's saved data";
        dict[NSLocalizedFailureReasonErrorKey] = failureReason;
        dict[NSUnderlyingErrorKey] = error;
        error = [NSError errorWithDomain:@"YOUR_ERROR_DOMAIN" code:9999 userInfo:dict];
        // Replace this with code to handle the error appropriately.
        // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
        NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
        abort();
    }
    
    return _persistentStoreCoordinator;
}


- (NSManagedObjectContext *)managedObjectContext {
    // Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.)
    
    // 懒加载(getter 方法)
    if (_managedObjectContext != nil) {
        return _managedObjectContext;
    }
    
    NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
    if (!coordinator) {
        return nil;
    }
    _managedObjectContext = [[NSManagedObjectContext alloc] init];
    [_managedObjectContext setPersistentStoreCoordinator:coordinator];
    return _managedObjectContext;
}

#pragma mark - Core Data Saving support

- (void)saveContext {
    NSManagedObjectContext *managedObjectContext = self.managedObjectContext;
    if (managedObjectContext != nil) {
        NSError *error = nil;
        if ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) {
            // Replace this implementation with code to handle the error appropriately.
            // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
            NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
            abort();
        }
    }
}

@end
